The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Generally, while a vehicle is being driven, a combustion noise is generated in an engine compartment of the vehicle and flows into an interior of the vehicle.
Such a combustion noise may be generated and propagate into the interior of the vehicle in various magnitudes depending on opening angles of engine valves associated with an engine rotation speed and an effort of an accelerator pedal, the number of passengers, or various temperature conditions of the interior of the vehicle.
The combustion noise is generated as a low frequency combustion noise or a high frequency combustion noise depending on a driving condition of the vehicle. The low frequency combustion noise may be reduced by calculating a phase of the low frequency combustion noise and then outputting a reverse-phase sound through a speaker installed in the interior of the vehicle.
However, it is difficult to effectively reduce a high frequency combustion noise generated in the engine compartment of the vehicle. Accordingly, while a vehicle is being driven, a driver may feel a sense of fatigue due to the high frequency combustion noise.